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Mike Brown's website lists it as a possible dwarf planet with a diameter of 343 km based on an assumed albedo of 0.04.[5] The albedo is expected to be low because the object has a blue (neutral) color.[5] But if the albedo is higher the object could be much smaller. Assuming a generic trans-Neptunian albedo of 0.09, it is about 270 km in diameter.[7] But because its true albedo is unknown and it has an absolute magnitude (H) of 6.2,[4] it could be anywhere from about 150 to 340 km in diameter.[6]

Given the orbital eccentricity of this object, different epochs can generate quite different heliocentric unperturbed two-bodybest-fit solutions to the aphelion (maximum distance from the Sun) of this object.[b] With a 2007 epoch the object had an approximate period of about 10,611 years with aphelion at 930 AU.[2] But using a 2011 epoch shows a period of about 13,304 years with aphelion at 1087 AU.[4] For objects at such high eccentricity, the Sun's barycentric coordinates are more stable than heliocentric coordinates.[10] Using JPL Horizons with an observed orbital arc of only 2 years, the barycentric orbital elements for epoch 2008-May-14 generate a semi-major axis of 501 AU and a period of 11,200 years.[3] For comparison, probable dwarf planetSedna has a barycentric semi-major axis of 506 AU and a period of 11,400 years.[3] Both (308933) 2006 SQ372 and (87269) 2000 OO67 take longer than Sedna and 2007 TG422 to orbit the Sun using barycentric coordinates.

2007 TG422 has been observed 34 times over five years and has an uncertainty parameter of 2.[4] It has not been observed since 2013.[4]